Merge branch '00.00-inst' of git://github.com/skeggsb/linux into drm-fixes
[platform/kernel/linux-starfive.git] / lib / logic_pio.c
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2017 HiSilicon Limited, All Rights Reserved.
4  * Author: Gabriele Paoloni <gabriele.paoloni@huawei.com>
5  * Author: Zhichang Yuan <yuanzhichang@hisilicon.com>
6  * Author: John Garry <john.garry@huawei.com>
7  */
8
9 #define pr_fmt(fmt)     "LOGIC PIO: " fmt
10
11 #include <linux/of.h>
12 #include <linux/io.h>
13 #include <linux/logic_pio.h>
14 #include <linux/mm.h>
15 #include <linux/rculist.h>
16 #include <linux/sizes.h>
17 #include <linux/slab.h>
18
19 /* The unique hardware address list */
20 static LIST_HEAD(io_range_list);
21 static DEFINE_MUTEX(io_range_mutex);
22
23 /* Consider a kernel general helper for this */
24 #define in_range(b, first, len)        ((b) >= (first) && (b) < (first) + (len))
25
26 /**
27  * logic_pio_register_range - register logical PIO range for a host
28  * @new_range: pointer to the IO range to be registered.
29  *
30  * Returns 0 on success, the error code in case of failure.
31  * If the range already exists, -EEXIST will be returned, which should be
32  * considered a success.
33  *
34  * Register a new IO range node in the IO range list.
35  */
36 int logic_pio_register_range(struct logic_pio_hwaddr *new_range)
37 {
38         struct logic_pio_hwaddr *range;
39         resource_size_t start;
40         resource_size_t end;
41         resource_size_t mmio_end = 0;
42         resource_size_t iio_sz = MMIO_UPPER_LIMIT;
43         int ret = 0;
44
45         if (!new_range || !new_range->fwnode || !new_range->size ||
46             (new_range->flags == LOGIC_PIO_INDIRECT && !new_range->ops))
47                 return -EINVAL;
48
49         start = new_range->hw_start;
50         end = new_range->hw_start + new_range->size;
51
52         mutex_lock(&io_range_mutex);
53         list_for_each_entry(range, &io_range_list, list) {
54                 if (range->fwnode == new_range->fwnode) {
55                         /* range already there */
56                         ret = -EEXIST;
57                         goto end_register;
58                 }
59                 if (range->flags == LOGIC_PIO_CPU_MMIO &&
60                     new_range->flags == LOGIC_PIO_CPU_MMIO) {
61                         /* for MMIO ranges we need to check for overlap */
62                         if (start >= range->hw_start + range->size ||
63                             end < range->hw_start) {
64                                 mmio_end = range->io_start + range->size;
65                         } else {
66                                 ret = -EFAULT;
67                                 goto end_register;
68                         }
69                 } else if (range->flags == LOGIC_PIO_INDIRECT &&
70                            new_range->flags == LOGIC_PIO_INDIRECT) {
71                         iio_sz += range->size;
72                 }
73         }
74
75         /* range not registered yet, check for available space */
76         if (new_range->flags == LOGIC_PIO_CPU_MMIO) {
77                 if (mmio_end + new_range->size - 1 > MMIO_UPPER_LIMIT) {
78                         /* if it's too big check if 64K space can be reserved */
79                         if (mmio_end + SZ_64K - 1 > MMIO_UPPER_LIMIT) {
80                                 ret = -E2BIG;
81                                 goto end_register;
82                         }
83                         new_range->size = SZ_64K;
84                         pr_warn("Requested IO range too big, new size set to 64K\n");
85                 }
86                 new_range->io_start = mmio_end;
87         } else if (new_range->flags == LOGIC_PIO_INDIRECT) {
88                 if (iio_sz + new_range->size - 1 > IO_SPACE_LIMIT) {
89                         ret = -E2BIG;
90                         goto end_register;
91                 }
92                 new_range->io_start = iio_sz;
93         } else {
94                 /* invalid flag */
95                 ret = -EINVAL;
96                 goto end_register;
97         }
98
99         list_add_tail_rcu(&new_range->list, &io_range_list);
100
101 end_register:
102         mutex_unlock(&io_range_mutex);
103         return ret;
104 }
105
106 /**
107  * logic_pio_unregister_range - unregister a logical PIO range for a host
108  * @range: pointer to the IO range which has been already registered.
109  *
110  * Unregister a previously-registered IO range node.
111  */
112 void logic_pio_unregister_range(struct logic_pio_hwaddr *range)
113 {
114         mutex_lock(&io_range_mutex);
115         list_del_rcu(&range->list);
116         mutex_unlock(&io_range_mutex);
117         synchronize_rcu();
118 }
119
120 /**
121  * find_io_range_by_fwnode - find logical PIO range for given FW node
122  * @fwnode: FW node handle associated with logical PIO range
123  *
124  * Returns pointer to node on success, NULL otherwise.
125  *
126  * Traverse the io_range_list to find the registered node for @fwnode.
127  */
128 struct logic_pio_hwaddr *find_io_range_by_fwnode(struct fwnode_handle *fwnode)
129 {
130         struct logic_pio_hwaddr *range, *found_range = NULL;
131
132         rcu_read_lock();
133         list_for_each_entry_rcu(range, &io_range_list, list) {
134                 if (range->fwnode == fwnode) {
135                         found_range = range;
136                         break;
137                 }
138         }
139         rcu_read_unlock();
140
141         return found_range;
142 }
143
144 /* Return a registered range given an input PIO token */
145 static struct logic_pio_hwaddr *find_io_range(unsigned long pio)
146 {
147         struct logic_pio_hwaddr *range, *found_range = NULL;
148
149         rcu_read_lock();
150         list_for_each_entry_rcu(range, &io_range_list, list) {
151                 if (in_range(pio, range->io_start, range->size)) {
152                         found_range = range;
153                         break;
154                 }
155         }
156         rcu_read_unlock();
157
158         if (!found_range)
159                 pr_err("PIO entry token 0x%lx invalid\n", pio);
160
161         return found_range;
162 }
163
164 /**
165  * logic_pio_to_hwaddr - translate logical PIO to HW address
166  * @pio: logical PIO value
167  *
168  * Returns HW address if valid, ~0 otherwise.
169  *
170  * Translate the input logical PIO to the corresponding hardware address.
171  * The input PIO should be unique in the whole logical PIO space.
172  */
173 resource_size_t logic_pio_to_hwaddr(unsigned long pio)
174 {
175         struct logic_pio_hwaddr *range;
176
177         range = find_io_range(pio);
178         if (range)
179                 return range->hw_start + pio - range->io_start;
180
181         return (resource_size_t)~0;
182 }
183
184 /**
185  * logic_pio_trans_hwaddr - translate HW address to logical PIO
186  * @fwnode: FW node reference for the host
187  * @addr: Host-relative HW address
188  * @size: size to translate
189  *
190  * Returns Logical PIO value if successful, ~0UL otherwise
191  */
192 unsigned long logic_pio_trans_hwaddr(struct fwnode_handle *fwnode,
193                                      resource_size_t addr, resource_size_t size)
194 {
195         struct logic_pio_hwaddr *range;
196
197         range = find_io_range_by_fwnode(fwnode);
198         if (!range || range->flags == LOGIC_PIO_CPU_MMIO) {
199                 pr_err("IO range not found or invalid\n");
200                 return ~0UL;
201         }
202         if (range->size < size) {
203                 pr_err("resource size %pa cannot fit in IO range size %pa\n",
204                        &size, &range->size);
205                 return ~0UL;
206         }
207         return addr - range->hw_start + range->io_start;
208 }
209
210 unsigned long logic_pio_trans_cpuaddr(resource_size_t addr)
211 {
212         struct logic_pio_hwaddr *range;
213
214         rcu_read_lock();
215         list_for_each_entry_rcu(range, &io_range_list, list) {
216                 if (range->flags != LOGIC_PIO_CPU_MMIO)
217                         continue;
218                 if (in_range(addr, range->hw_start, range->size)) {
219                         unsigned long cpuaddr;
220
221                         cpuaddr = addr - range->hw_start + range->io_start;
222
223                         rcu_read_unlock();
224                         return cpuaddr;
225                 }
226         }
227         rcu_read_unlock();
228
229         pr_err("addr %pa not registered in io_range_list\n", &addr);
230
231         return ~0UL;
232 }
233
234 #if defined(CONFIG_INDIRECT_PIO) && defined(PCI_IOBASE)
235 #define BUILD_LOGIC_IO(bwl, type)                                       \
236 type logic_in##bwl(unsigned long addr)                                  \
237 {                                                                       \
238         type ret = (type)~0;                                            \
239                                                                         \
240         if (addr < MMIO_UPPER_LIMIT) {                                  \
241                 ret = _in##bwl(addr);                                   \
242         } else if (addr >= MMIO_UPPER_LIMIT && addr < IO_SPACE_LIMIT) { \
243                 struct logic_pio_hwaddr *entry = find_io_range(addr);   \
244                                                                         \
245                 if (entry)                                              \
246                         ret = entry->ops->in(entry->hostdata,           \
247                                         addr, sizeof(type));            \
248                 else                                                    \
249                         WARN_ON_ONCE(1);                                \
250         }                                                               \
251         return ret;                                                     \
252 }                                                                       \
253                                                                         \
254 void logic_out##bwl(type value, unsigned long addr)                     \
255 {                                                                       \
256         if (addr < MMIO_UPPER_LIMIT) {                                  \
257                 _out##bwl(value, addr);                         \
258         } else if (addr >= MMIO_UPPER_LIMIT && addr < IO_SPACE_LIMIT) { \
259                 struct logic_pio_hwaddr *entry = find_io_range(addr);   \
260                                                                         \
261                 if (entry)                                              \
262                         entry->ops->out(entry->hostdata,                \
263                                         addr, value, sizeof(type));     \
264                 else                                                    \
265                         WARN_ON_ONCE(1);                                \
266         }                                                               \
267 }                                                                       \
268                                                                         \
269 void logic_ins##bwl(unsigned long addr, void *buffer,                   \
270                     unsigned int count)                                 \
271 {                                                                       \
272         if (addr < MMIO_UPPER_LIMIT) {                                  \
273                 reads##bwl(PCI_IOBASE + addr, buffer, count);           \
274         } else if (addr >= MMIO_UPPER_LIMIT && addr < IO_SPACE_LIMIT) { \
275                 struct logic_pio_hwaddr *entry = find_io_range(addr);   \
276                                                                         \
277                 if (entry)                                              \
278                         entry->ops->ins(entry->hostdata,                \
279                                 addr, buffer, sizeof(type), count);     \
280                 else                                                    \
281                         WARN_ON_ONCE(1);                                \
282         }                                                               \
283                                                                         \
284 }                                                                       \
285                                                                         \
286 void logic_outs##bwl(unsigned long addr, const void *buffer,            \
287                      unsigned int count)                                \
288 {                                                                       \
289         if (addr < MMIO_UPPER_LIMIT) {                                  \
290                 writes##bwl(PCI_IOBASE + addr, buffer, count);          \
291         } else if (addr >= MMIO_UPPER_LIMIT && addr < IO_SPACE_LIMIT) { \
292                 struct logic_pio_hwaddr *entry = find_io_range(addr);   \
293                                                                         \
294                 if (entry)                                              \
295                         entry->ops->outs(entry->hostdata,               \
296                                 addr, buffer, sizeof(type), count);     \
297                 else                                                    \
298                         WARN_ON_ONCE(1);                                \
299         }                                                               \
300 }
301
302 BUILD_LOGIC_IO(b, u8)
303 EXPORT_SYMBOL(logic_inb);
304 EXPORT_SYMBOL(logic_insb);
305 EXPORT_SYMBOL(logic_outb);
306 EXPORT_SYMBOL(logic_outsb);
307
308 BUILD_LOGIC_IO(w, u16)
309 EXPORT_SYMBOL(logic_inw);
310 EXPORT_SYMBOL(logic_insw);
311 EXPORT_SYMBOL(logic_outw);
312 EXPORT_SYMBOL(logic_outsw);
313
314 BUILD_LOGIC_IO(l, u32)
315 EXPORT_SYMBOL(logic_inl);
316 EXPORT_SYMBOL(logic_insl);
317 EXPORT_SYMBOL(logic_outl);
318 EXPORT_SYMBOL(logic_outsl);
319
320 #endif /* CONFIG_INDIRECT_PIO && PCI_IOBASE */